<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<link rel="STYLESHEET" href="lib.css" type='text/css' />
<link rel="SHORTCUT ICON" href="../icons/pyfav.png" type="image/png" />
<link rel='start' href='../index.html' title='Python documentation Index' />
<link rel="first" href="lib.html" title='Python library Reference' />
<link rel='contents' href='contents.html' title="Contents" />
<link rel='index' href='genindex.html' title='Index' />
<link rel='last' href='about.html' title='About this document...' />
<link rel='help' href='about.html' title='About this document...' />
<link rel="next" href="comparisons.html" />
<link rel="prev" href="truth.html" />
<link rel="parent" href="types.html" />
<link rel="next" href="comparisons.html" />
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name='aesop' content='information' />
<title>3.2 Boolean Operations -- and, or, not </title>
</head>
<body>
<div class="navigation">
<div id='top-navigation-panel' xml:id='top-navigation-panel'>
<table align="center" width="100%" cellpadding="0" cellspacing="2">
<tr>
<td class='online-navigation'><a rel="prev" title="3.1 truth Value Testing"
  href="truth.html"><img src='../icons/previous.png'
  border='0' height='32'  alt='Previous Page' width='32' /></a></td>
<td class='online-navigation'><a rel="parent" title="3. built-in Types"
  href="types.html"><img src='../icons/up.png'
  border='0' height='32'  alt='Up one Level' width='32' /></a></td>
<td class='online-navigation'><a rel="next" title="3.3 Comparisons"
  href="comparisons.html"><img src='../icons/next.png'
  border='0' height='32'  alt='Next Page' width='32' /></a></td>
<td align="center" width="100%">Python Library Reference</td>
<td class='online-navigation'><a rel="contents" title="Table of Contents"
  href="contents.html"><img src='../icons/contents.png'
  border='0' height='32'  alt='Contents' width='32' /></a></td>
<td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png'
  border='0' height='32'  alt='Module Index' width='32' /></a></td>
<td class='online-navigation'><a rel="index" title="Index"
  href="genindex.html"><img src='../icons/index.png'
  border='0' height='32'  alt='Index' width='32' /></a></td>
</tr></table>
<div class='online-navigation'>
<b class="navlabel">Previous:</b>
<a class="sectref" rel="prev" href="truth.html">3.1 Truth Value Testing</a>
<b class="navlabel">Up:</b>
<a class="sectref" rel="parent" href="types.html">3. Built-in Types</a>
<b class="navlabel">Next:</b>
<a class="sectref" rel="next" href="comparisons.html">3.3 Comparisons</a>
</div>
<hr /></div>
</div>
<!--End of Navigation Panel-->

<h1><a name="SECTION005200000000000000000"></a><a name="boolean"></a>
<br>
3.2 Boolean Operations --
	    <tt class="keyword">and</tt>, <tt class="keyword">or</tt>, <tt class="keyword">not</tt>
	    
</h1>

<p>
These are the Boolean operations, ordered by ascending priority:
<a id='l2h-161' xml:id='l2h-161'></a>
<p>
<div class="center"><table class="realtable">
  <thead>
    <tr>
      <th class="center">Operation</th>
      <th class="left"  >Result</th>
      <th class="center">Notes</th>
      </tr>
    </thead>
  <tbody>
    <tr><td class="center" valign="baseline"><code><var>x</var> or <var>y</var></code></td>
        <td class="left"  >if <var>x</var> is false, then <var>y</var>, else <var>x</var></td>
        <td class="center">(1)</td></tr>
    <tr><td class="center" valign="baseline"><code><var>x</var> and <var>y</var></code></td>
        <td class="left"  >if <var>x</var> is false, then <var>x</var>, else <var>y</var></td>
        <td class="center">(1)</td></tr>
  
    <tr><td class="center" valign="baseline"><code>not <var>x</var></code></td>
        <td class="left"  >if <var>x</var> is false, then <code>True</code>, else <code>False</code></td>
        <td class="center">(2)</td></tr></tbody>
</table></div>
<a id='l2h-162' xml:id='l2h-162'></a><a id='l2h-163' xml:id='l2h-163'></a><a id='l2h-164' xml:id='l2h-164'></a>
<p>
Notes:

<p>
<dl>
<dt><strong>(1)</strong></dt>
<dd>These only evaluate their second argument if needed for their outcome.

<p>
</dd>
<dt><strong>(2)</strong></dt>
<dd>"<tt class="samp">not</tt>" has a lower priority than non-Boolean operators, so
<code>not <var>a</var> == <var>b</var></code> is interpreted as <code>not (<var>a</var> ==
<var>b</var>)</code>, and <code><var>a</var> == not <var>b</var></code> is a syntax error.

<p>
</dd>
</dl>

<p>

<div class="navigation">
<div class='online-navigation'>
<p></p><hr />
<table align="center" width="100%" cellpadding="0" cellspacing="2">
<tr>
<td class='online-navigation'><a rel="prev" title="3.1 truth Value Testing"
  href="truth.html"><img src='../icons/previous.png'
  border='0' height='32'  alt='Previous Page' width='32' /></a></td>
<td class='online-navigation'><a rel="parent" title="3. built-in Types"
  href="types.html"><img src='../icons/up.png'
  border='0' height='32'  alt='Up one Level' width='32' /></a></td>
<td class='online-navigation'><a rel="next" title="3.3 Comparisons"
  href="comparisons.html"><img src='../icons/next.png'
  border='0' height='32'  alt='Next Page' width='32' /></a></td>
<td align="center" width="100%">Python Library Reference</td>
<td class='online-navigation'><a rel="contents" title="Table of Contents"
  href="contents.html"><img src='../icons/contents.png'
  border='0' height='32'  alt='Contents' width='32' /></a></td>
<td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png'
  border='0' height='32'  alt='Module Index' width='32' /></a></td>
<td class='online-navigation'><a rel="index" title="Index"
  href="genindex.html"><img src='../icons/index.png'
  border='0' height='32'  alt='Index' width='32' /></a></td>
</tr></table>
<div class='online-navigation'>
<b class="navlabel">Previous:</b>
<a class="sectref" rel="prev" href="truth.html">3.1 Truth Value Testing</a>
<b class="navlabel">Up:</b>
<a class="sectref" rel="parent" href="types.html">3. Built-in Types</a>
<b class="navlabel">Next:</b>
<a class="sectref" rel="next" href="comparisons.html">3.3 Comparisons</a>
</div>
</div>
<hr />
<span class="release-info">Release 2.5.1, documentation updated on 18th April, 2007.</span>
</div>
<!--End of Navigation Panel-->
<address>
See <i><a href="about.html">About this document...</a></i> for information on suggesting changes.
</address>
</body>
</html>
